WEBVTT NOTE Phone Operating on HF 1 00:00:00.000 --> 00:00:25.414 Which sideband, and why. One rule with one exception, and the pool asks it four times. Bands, 160, 75, and 40 metres; Sideband, lower (LSB). Bands, 20, 17, 15, 12, 10 metres; Sideband, upper (USB). 2 00:00:25.414 --> 00:00:40.250 Bands, VHF and UHF SSB; Sideband, upper (USB). The dividing line falls around 10 MHz: below it, LSB; above it, USB. 3 00:00:40.250 --> 00:00:50.210 Question. Why do most amateur stations use lower sideband on the 160-, 75-, and 40-meter bands? 4 00:00:51.110 --> 00:00:55.670 Answer. It is commonly accepted amateur practice. 5 00:00:56.270 --> 00:01:06.734 Convention, not rule. There is no technical reason and no regulation, early equipment made it convenient, and it stuck. 6 00:01:06.734 --> 00:01:18.430 Using the wrong one is legal and renders your voice unintelligible, which is the practical enforcement. Why SSB rather than AM or FM. 7 00:01:18.430 --> 00:01:26.230 Question. Which mode of voice communication is most commonly used on the HF amateur bands? 8 00:01:27.130 --> 00:01:30.370 Answer. Single sideband. 9 00:01:30.970 --> 00:01:38.250 Question. Which of the following statements is true of single sideband (SSB)? 10 00:01:39.150 --> 00:01:47.430 Answer. Only one sideband is transmitted; the other sideband and carrier are suppressed. 11 00:01:48.030 --> 00:01:58.670 Question. Which of the following is an advantage of using single sideband, as compared to other analog voice modes on the HF amateur bands? 12 00:01:59.570 --> 00:02:05.170 Answer. Less bandwidth used and greater power efficiency. 13 00:02:05.770 --> 00:02:22.709 Both halves matter. AM transmits a carrier plus two identical sidebands: two thirds of the power goes into the carrier, which carries no information, and the duplicate sideband wastes bandwidth. 14 00:02:22.709 --> 00:02:37.028 SSB throws away both and puts everything into the one sideband that matters, about a third of the bandwidth and a large improvement in effective power. Setting ALC. 15 00:02:37.028 --> 00:02:44.988 Question. What control is typically adjusted for proper ALC setting on a single sideband transceiver? 16 00:02:45.888 --> 00:02:50.648 Answer. Transmit audio or microphone gain. 17 00:02:51.248 --> 00:03:06.284 Automatic Level Control limits drive to keep the transmitter linear. It is a safety net, not an operating control: the correct setting has ALC just barely indicating on voice peaks. 18 00:03:06.284 --> 00:03:22.150 Turn the microphone gain up until ALC shows heavy action and you are driving the transmitter into distortion, flat-topping, splatter, and a signal that is wider and less readable, not louder. 19 00:03:22.150 --> 00:03:31.703 Reduce it until ALC only flickers. This is the single most common self-inflicted signal problem on HF. Breaking in. 20 00:03:31.703 --> 00:03:37.639 Question. What is the recommended way to break into a phone contact? 21 00:03:38.539 --> 00:03:42.243 Answer. Say your call sign once. 22 00:03:42.843 --> 00:03:56.403 Once. Not "break", not "break break", not your call sign three times. One call sign, in a gap, and then wait. VOX. 23 00:03:56.403 --> 00:04:04.405 Question. Which of the following statements is true of VOX operation versus PTT operation? 24 00:04:05.305 --> 00:04:09.545 Answer. It allows "hands free" operation. 25 00:04:10.145 --> 00:04:25.883 That is the advantage; the disadvantages are worth knowing too. VOX triggers on room noise, clips the first syllable while it decides, and holds the transmitter up during pauses. 26 00:04:25.883 --> 00:04:34.105 It is excellent for a quiet room and mobile operating, and poor in a noisy one. DX etiquette. 27 00:04:34.105 --> 00:04:44.248 Question. Generally, who should respond to a station in the contiguous 48 states calling "CQ DX"? 28 00:04:45.148 --> 00:04:50.468 Answer. Any stations outside the lower 48 states. 29 00:04:51.068 --> 00:05:05.748 "CQ DX" means the caller wants distance, and answering from three states away wastes everyone's time, including yours, since they will not work you. The corresponding band-plan convention: 30 00:05:05.748 --> 00:05:22.009 Question. What is the voluntary band plan restriction for US stations transmitting within the 48 contiguous states in the 50.1 MHz to 50.125 MHz band segment? 31 00:05:22.909 --> 00:05:30.469 Answer. Only contacts with stations not within the 48 contiguous states. 32 00:05:31.069 --> 00:05:49.290 That 25 kHz at the bottom of 6 metres is reserved by voluntary agreement for DX work. Domestic contacts there are legal and antisocial, exactly the character of every band plan. Check yourself. 33 00:05:49.290 --> 00:06:08.549 You are on 7.200 MHz for a voice contact. Which sideband? Your ALC meter pins on every syllable. What is happening and what do you adjust? A station in Ohio calls "CQ DX". Should you answer from Michigan? 34 00:06:14.549 --> 00:06:36.479 Lower sideband, 40 metres, below the 10 MHz convention line. You are overdriving the transmitter: distortion and splatter, not extra volume. Reduce transmit audio or microphone gain until ALC barely indicates. No. 35 00:06:36.479 --> 00:06:44.612 They want stations outside the lower 48. Answering wastes their time and yours.